Monday my 2017 F350 6.7L Powerstroke is going to the shop for the 3rd time for P0402 (Exhaust Gas Recirculation Flow Excessive). The first time they performed the TSB to reprogram, the second time the replaced the mass air flow sensor and the code came back within 200 miles.

Any thoughts?

 

It’s an EGR code. I don’t understand why they would do anything with the mass airflow.I question your dealers mechanical knowledge. Try another dealer.

 

I agree. The service rep did not have a good explanation when questioned.

 

Normally happens with excessive idling, is this truck high on idle hours?

 

I would be checking the EGR cooler for becoming plugged up.

 

The last one I changed with this code had a wet goo in the cooler and very plugged and stuck in constant regen.

 

The truck does not idle much. 739 engine hours. 108 idle hours.

 

Truck is in the shop for the 3rd time right now for this code. It has been there 3 days. All I have been told is that there is an electrical issue they cannot find and the service manager will be calling me to explain the plan.

This is getting frustrating. Thoughts?

 

Should have deleted the BS right away.

I did and will never have the issues your having.

Sorry, I know that Doesnt help you now.

Flow too high could mean different things as the codes thrown dont always mean exactly what its saying or doesnt mean that sensor is bad. Something else before or down the line could be causing the code from said sensor.
Flow too high could be a restricting in the EGR system causing the gasses to speed up. ? I dont know how else the flow could increase other then maybe the valve is opening too far or too much for the amount of proper EGR. I would then think there would be more codes down the line from an overfueling type situation. If the amount of EGR is too high, then the effective displacement of the engine is reduced too much. And then the normal amount of fuel would be too much causing a rich burning situation which would also cause more frequent regens. EGR has a lot of effects on rich/lean and displacement since EGR is an inert gas(doesnt burn).

The system could be clogged. The EGR supply tube, the cooler, the valve. Many things. IMO The entire EGR system should be disassembled and thoroughly cleaned.

Another thought could be a clogged or restricted CAT/DPF thats causing some higher then normal back pressure and forcing the Exhaust gasses into the egr system with excessive pressure.

Or we could be dealing with a corroded wire harness plug causing codes to flip.

Most likely a Kind of a long “process of elimination” is going to be how the problem & fix are discovered. I wouldnt be expecting any one single trip to the dumb dumbs at a Ford shop to fix the problem. Set your expectation low and hope for the best🤷🏼‍♂️

 

What was the problem and did you get it worked out? I have the same code after changing the CAC hose for a tear in it.

Thank you.

 

I am wondering what the resolution was? I am getting this same code and it is the same as jetdawg, mine started after I had to change the CAC hose for a crack.

Thanks,

Joe

 

https://www.ford-trucks.com/forums/1...upgrade-3.html

 

I cleared the code while driving it about 30 times. I could tell it was going in limp mode because I wouldn't get above 20 psi boost. The check engine light would not come on while it was a pending code but would put it in limp mode. Soon after it would become a confirmed and permanent trouble code. Ultimately, I drove it like I stole it and cleared it while it was in limp mode prior to becoming a confirmed trouble code. I used forscan and blue driver to monitor EGR, MAP, MAF while I was driving as well. I removed the air filter, MAP Sensor, MAF Sensor and cleaned everything and it didn't go away. Exercise the engine and be patient is my only suggestion. The code went away finally after about 2 tanks of fuel. I resorted to bringing a can of PB Blaster with me and had been spraying the EGR bolts after every trip getting ready to pull the EGR and Clean/Delete it.

Hope this helps you out.